The hype around Yahoo's month-long roll out of its new logo may have you wondering if your company is ready for a new design, too.

"A logo is your business's public face," says Patrick Llewellyn, president and CEO of 99designs, a graphic design firm where businesses hold online contests to find new logos. "If it doesn't represent your business at its core, it's time for a change."

Llewellyn says there are several indicators that a small business needs a new logo. Here are five signs that it's time to work on a new design:

1. Your logo doesn't adapt well to modern media.
If your logo was designed for your storefront 15 years ago, it might not be optimized to work well on a website or on social media platforms such as Facebook and Twitter.

"It may have looked great on a sign or in a Yellow Pages ad, but businesses today promote themselves in a lot of new ways," says Llewellyn. "It's important that the logo works across several mediums."

Llewellyn says entrepreneurs should ask themselves these questions: Can the logo be sized up or down and still be readable? Does it look good in black and white? Can you derive an icon from it? Does it make an appealing button for a mobile app? If the answer to any of these questions is no, it may be time for a new logo design.

2. Your logo doesn't represent your current business.
Over time, most business evolve. It's not uncommon for entrepreneurs to start out with one product or service, then grow and diversify into something quite different. If your logo doesn't reflect what you currently offer, it's time for a rebranding, says Llewellyn.

"A logo isn't about where your business was in the past," he says. "A logo should be aspirational, capturing the essence of your business today as well as where you're headed in the future."

3. Your logo was a do-it-yourself project.
If you created your logo or had a friend of family member create it, it may be time for a professional to step in.

"Companies such as Apple have become very successful due in part to their emphasis on design," says Llewellyn. "As a result, our world has increased its expectations of design."

He says if you're not receiving compliments on your logo, it probably needs to be redesigned.

4. Your logo isn't as appealing as your competition's.
Llewellyn says social media review sites such as Yelp have made the business world increasingly competitive. He suggests looking at your competitions' logo designs.

"If their logos are more appealing, it's a good indicator that yours needs an update or change," he says.

If you're not sure, compare your social media following to your competitors'. If they have more fans and followers, it may be time for a new design. "Don't underestimate the impact of good design," he says.

5. Your logo is too complex.
Llewellyn says the growing trend in logos has been towards simplification in design. "Gradients and drop shadows used to be popular in logos, but these techniques are starting to look dated," he says. "They're also difficult to translate across some mediums."

Instead, choose a simple logo design that utilizes up to three colors. Choose a flat matte look. "One indicator that your logo is simple and effective is if it can be used in a transparent form as a background and still be recognizable," Llewellyn says.